我該如何使用方法？

Question

我是java的初學者。在我的程序中，我寫了一個隨機n數組的數組，偶數的索引，奇數元素，反轉元素，第一個，最後一個元素的代碼。現在我想用獨立的方法來實現我的程序。我該怎麼辦
？

public class Rand { 

     public static void main(String[] args) { 
      // TODO Auto-generated method stub 
      Scanner input = new Scanner (System.in); 
      System.out.print("Enter the number of values:"); 

       int[] values = new int[input.nextInt()]; 
       Random rand = new Random(); 
       for (int i = 0; i < values.length; i++) { 
       int n = rand.nextInt(20); 
       values[i] = n; 
       } 
       System.out.print("Array: "); 
       for (int i = 0; i < values.length; i++) { 
        System.out.print(" " + values[i]); 
       } 

       System.out.println(); 
       System.out.print("Even index: "); 
       for (int i = 0; i < values.length; i++) { 
        if (i % 2 == 0) { 
         System.out.print(" " +values[i]); 
        } 
       } 
       System.out.println(); 
       System.out.print("Odd element:"); 
       for (int i = 0; i < values.length; i++) { 
        if (values[i] % 2 != 0) { 
         System.out.print(" " + values[i]); 
        } 
       } 
       System.out.println(); 
       System.out.print("Reverse order:"); 
       for (int i = values.length - 1; i > -1; i--) { 
        System.out.print(" "+ values[i]); 
       } 
       System.out.println(); 
       System.out.print("First, middle and last element:"); 
       System.out.print(" " + values[0]); 

       if (values.length %2 ==0) 
       { 
        System.out.print(" " + values[(values.length /2)-1]); 
        System.out.print(" " + values[values.length /2]); 

       } 
       System.out.print(" " + values[values.length - 1]); 



     } 

    } 

Answer 1

很好的一個例子，你可以在你main

  Scanner input = new Scanner (System.in); 
     System.out.print("Enter the number of values:"); 

      int[] values = new int[input.nextInt()]; 
      Random rand = new Random(); 
      for (int i = 0; i < values.length; i++) { 
      int n = rand.nextInt(20); 
      values[i] = n; 
      } 

與

  int[] values = getValues(); 

其中getValues看起來像

private static int [] getValues() { 
    Scanner input = new Scanner (System.in); 
    System.out.print("Enter the number of values:"); 

     int[] values = new int[input.nextInt()]; 
     Random rand = new Random(); 
     for (int i = 0; i < values.length; i++) { 
     int n = rand.nextInt(20); 
     values[i] = n; 
     } 

     // lets also close the Scanner 
     input.close(); 
     return values;